(1) Field of the Invention
The present invention is related to a television signal processing system and more particularly to a system for processing a color television signal which can easily realize processing for obtaining a high quality picture in a receiver by means of accomplishing certain processing for a transmitting television signal on the basis of information related to image movement when generating a television signal for transmission.
(2) Description of Prior Art
In the present television signal processing system, various designs have been developed for transmitting picture information in a limited transmission band and obtaining adequate picture quality. For example, for scanning, there is the interlace scan wherein scanning lines of adjacent frames are between scanning lines of other frames. Further, an NTSC television system serves to multiply a chrominance signal on a frequency band of a luminance signal.
At present, there are proposed some methods for improving picture quality in a TV receiver, but there are some cases where the above-stated conventional television signal system techniques are a hindrance to improving picture quality, contrary to expectations.
For a high resolution television signal system which can retain the transmission band and the signal form of a conventional television signal and at the same time, receive and transmit a high-resolution picture, there is proposed a method having a full-compatibility with the present standard (European Patent Application, Application No. 841026958 Publication No. 0120,390 "Television signal transmission system").
This television signal processing system is designed to ameliorate picture quality by the method wherein, on the transmitting side, high-band frequency components of a luminance signal over a transmission band are frequency-converted as high resolution information and are then inserted in a gap between spectra of the conventional television signal so as to multiply the frequency for generating a television signal and, on the receiving side, these high-band frequency components are separated and regenerated so as to regenerate a wide band of a luminance signal. However, as stated after in detail, this system is very effective for a still picture but the quality of a moving picture is quite inferior since the picture originally belonging to a low frequency of luminance signal Y.sub.L is converted to a high frequency signal as high resolution information and is erroneously regenerated.
Namely, this known system has the disadvantage that a low-band frequency luminance signal in relation to a moving picture is erroneously regenerated as high resolution information so that the picture quality is adversely affected.
Furthermore, for a system for improving TV picture quality, there exists a processing system for obtaining a high quality picture by means of employing interpolating techniques for an interlace-scanned signal, doubling the number of scanning lines and converting the interlace-scanned signal into a line sequential scanning signal. But because of interpolation, this system is ineffective for improving picture quality of a moving picture.
Thus, there is known the technique wherein a detecting section for moving images is provided in a television receiver and signal processing is controlled in accordance with picture motion. However, since a motion detecting circuit is provided on the receiving side, such a television receiver is costly.